The University of California at San Francisco (UCSF) is planning to build a proton therapy facility as a part of its new Comprehensive Cancer Center. The UCSF Proton Facility will be installed in the lower levels of a new building housing research facilities for the Cancer Center, to be located at UCSF's Mount Zion Hospital and Medical Center site. UCSF and LBL are entering into an agreement to advance this project; LBL will design the accelerator, beam transport and beam delivery systems, will oversee their construction and will be responsible for commissioning and initial operation of the Proton Facility at Mount Zion. As construction of the accelerator systems will probably be finished at least one year prior to the new building's completion, the accelerator will be installed within the experimental area of the Bevalac, and connected to the currently-operating treatment facilities. This will allow for full commissioning of the accelerator, from initial operation to full readiness for clinical use of the proton beam, prior to its transport to its permanent location at Mount Zion. Work to be performed this coming year as part of this Grant application is critical to the success of this project. Very early in the year decisions will be made on the major specifications and architecture of the technical systems. The remainder of the time will be spent in full-scale design and costing activities, leading to the production of a Full Design Report. Detailed designs will emerge from very close interfacing between clinical, medical physics, accelerator physics and engineering personnel; final specifications for each element emerging during the course of the year as a result of design, function and cost optimization studies. The design report will include scope and costing of conventional aspects of the project as well; we will be working with A&E representatives of UCSF to integrate the UCSF Proton Facility into the Comprehensive Cancer Center plans. An analysis of regulatory requirements, and costs for compliance documents will be estimated as well. Finally, a model for operations of the facility will be developed, to identify required ongoing operations costs. The Full Design Report will be a blueprint for the entire UCSF Proton Facility, it will be a document essentially suitable as a bid package.